<!DOCTYPE html>
<html lang="en">
<head>
    <title>Show polygon information on click</title>
    <meta property="og:description" content="When a user clicks a polygon, show a popup containing more information." />
    <meta charset='utf-8'>
    <meta name="viewport" content="width=device-width, initial-scale=1">
    <link rel='stylesheet' href='https://unpkg.com/maplibre-gl@3.4.1/dist/maplibre-gl.css' />
    <script src='https://unpkg.com/maplibre-gl@3.4.1/dist/maplibre-gl.js'></script>
    <style>
        body { margin: 0; padding: 0; }
        html, body, #map { height: 100%; }
    </style>
</head>
<body>
<style>
    .maplibregl-popup {
        max-width: 400px;
        font: 12px/20px 'Helvetica Neue', Arial, Helvetica, sans-serif;
    }
</style>
<div id="map"></div>
<script>
    const map = new maplibregl.Map({
        container: 'map',
        style: 'https://api.maptiler.com/maps/streets/style.json?key=get_your_own_OpIi9ZULNHzrESv6T2vL',
        center: [-100.04, 38.907],
        zoom: 3
    });

    map.on('load', () => {
        // Add a source for the state polygons.
        map.addSource('states', {
            'type': 'geojson',
            'data': 'https://d2ad6b4ur7yvpq.cloudfront.net/naturalearth-3.3.0/ne_110m_admin_1_states_provinces_shp.geojson'
        });

        // Add a layer showing the state polygons.
        map.addLayer({
            'id': 'states-layer',
            'type': 'fill',
            'source': 'states',
            'paint': {
                'fill-color': 'rgba(200, 100, 240, 0.4)',
                'fill-outline-color': 'rgba(200, 100, 240, 1)'
            }
        });

        // When a click event occurs on a feature in the states layer, open a popup at the
        // location of the click, with description HTML from its properties.
        map.on('click', 'states-layer', (e) => {
            new maplibregl.Popup()
                .setLngLat(e.lngLat)
                .setHTML(e.features[0].properties.name)
                .addTo(map);
        });

        // Change the cursor to a pointer when the mouse is over the states layer.
        map.on('mouseenter', 'states-layer', () => {
            map.getCanvas().style.cursor = 'pointer';
        });

        // Change it back to a pointer when it leaves.
        map.on('mouseleave', 'states-layer', () => {
            map.getCanvas().style.cursor = '';
        });
    });
</script>
</body>
</html>
